Twice in the last three years something exotic has unexpectedly fluttered into my life, teased me for a minute or two, and then floated up and away over the tree tops. In each case I was relaxing in a lawn chair on a warm August afternoon, and in both instances I bolted into the house to get my camera and prepare for the digital capture of a subject that was moving constantly and erratically, wings blurred by rapid, perpetual motion.
If you live in the Deep South you will probably get a good laugh from this post, or quickly leave to search for something more interesting. The visitor was a Giant Swallowtail butterfly (Papilio cresphontes), a species that is quite common in the South but unfamiliar to most northerners. I’ve been chasing butterflies since old enough to walk but had never seen, or heard of, this species until 2011. Soon after that initial encounter, it was featured in the August, 2011 issue of the New York State Conservationist magazine in an article by Terry Mosher : “Swallowtail Surprise”. An older field guide to eastern butterflies lists my location in central New York as the extreme northern fringe of the range of this butterfly but sightings have increased throughout the Northeast in recent years. Climate change is no doubt an influencing factor in this trend. I’m also suspicious that “snow birds” – the millions of humans that migrate North to South in the winter – might have something to do with the distribution of the species.
Surprisingly, the Giant Swallowtail ranges far beyond the flower gardens, pine flats and Citrus groves of the South, occurring from southeastern Canada to South America. Adults nectar on many flowering plants, including Goldenrod and Phlox in the Northeast. The caterpillars (called “orangedogs” in the South) love plants in the Citrus family (in some cases to the point of being a pest), but also feed on a thicket-forming shrub found in this region: Northern Prickly-ash.
The nectaring flight pattern of a Giant Swallowtail is mesmerizing: flight movement is slow, but the wings, particularly the forewings, flutter constantly and rapidly as it bounces, hops and darts from flower to flower. The only pauses in rapid wing motion – mere fractions of a second – occur first when the butterfly is nectaring and again between flower visits.
Appropriately named, the Giant Swallowtail is among the largest butterflies in North America (some claim it’s the largest), with a wing span of about 6 inches (noticeably larger than the familiar Tiger Swallowtail).
“When we try to pick out anything by itself, we find it hitched to everything else in the universe.” – John Muir
Photos by NB Hunter. © All Rights Reserved.